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| author | Stefan Monnier <monnier@iro.umontreal.ca> | 2017-06-30 22:01:38 -0400 |
|---|---|---|
| committer | Stefan Monnier <monnier@iro.umontreal.ca> | 2017-06-30 22:01:38 -0400 |
| commit | 6fb45b7b368c8041936c52f2b2c261136c070721 (patch) | |
| tree | 936137a04840e4076f4838b2f591cb9542c8834a /lisp/emacs-lisp/cl-extra.el | |
| parent | 7618d29db36396fbd736672cadaca641186c1dc5 (diff) | |
| download | emacs-6fb45b7b368c8041936c52f2b2c261136c070721.tar.gz emacs-6fb45b7b368c8041936c52f2b2c261136c070721.tar.bz2 emacs-6fb45b7b368c8041936c52f2b2c261136c070721.zip | |
* lisp/emacs-lisp/cl-extra.el (cl--random-state): New defstruct
(cl--random-state, cl--random-time): Move from cl-lib.el.
(cl-random): Use struct accessors.
(cl-random-state-p): Remove, provided by the defstruct.
(cl-make-random-state): Rewrite to struct constructor.
Diffstat (limited to 'lisp/emacs-lisp/cl-extra.el')
| -rw-r--r-- | lisp/emacs-lisp/cl-extra.el | 39 |
1 files changed, 24 insertions, 15 deletions
diff --git a/lisp/emacs-lisp/cl-extra.el b/lisp/emacs-lisp/cl-extra.el index 3852ceb6c31..99df209d1a2 100644 --- a/lisp/emacs-lisp/cl-extra.el +++ b/lisp/emacs-lisp/cl-extra.el @@ -437,22 +437,38 @@ as an integer unless JUNK-ALLOWED is non-nil." ;; Random numbers. +(defun cl--random-time () + (let* ((time (copy-sequence (current-time-string))) (i (length time)) (v 0)) + (while (>= (cl-decf i) 0) (setq v (+ (* v 3) (aref time i)))) + v)) + +;;;###autoload (autoload 'cl-random-state-p "cl-extra") +(cl-defstruct (cl--random-state + (:copier nil) + (:predicate cl-random-state-p) + (:constructor nil) + (:constructor cl--make-random-state (vec))) + (i -1) (j 30) vec) + +(defvar cl--random-state (cl--make-random-state (cl--random-time))) + ;;;###autoload (defun cl-random (lim &optional state) "Return a random nonnegative number less than LIM, an integer or float. Optional second arg STATE is a random-state object." (or state (setq state cl--random-state)) ;; Inspired by "ran3" from Numerical Recipes. Additive congruential method. - (let ((vec (aref state 3))) + (let ((vec (cl--random-state-vec state))) (if (integerp vec) (let ((i 0) (j (- 1357335 (abs (% vec 1357333)))) (k 1)) - (aset state 3 (setq vec (make-vector 55 nil))) + (setf (cl--random-state-vec state) + (setq vec (make-vector 55 nil))) (aset vec 0 j) (while (> (setq i (% (+ i 21) 55)) 0) (aset vec i (setq j (prog1 k (setq k (- j k)))))) (while (< (setq i (1+ i)) 200) (cl-random 2 state)))) - (let* ((i (aset state 1 (% (1+ (aref state 1)) 55))) - (j (aset state 2 (% (1+ (aref state 2)) 55))) + (let* ((i (cl-callf (lambda (x) (% (1+ x) 55)) (cl--random-state-i state))) + (j (cl-callf (lambda (x) (% (1+ x) 55)) (cl--random-state-j state))) (n (logand 8388607 (aset vec i (- (aref vec i) (aref vec j)))))) (if (integerp lim) (if (<= lim 512) (% n lim) @@ -466,17 +482,10 @@ Optional second arg STATE is a random-state object." (defun cl-make-random-state (&optional state) "Return a copy of random-state STATE, or of the internal state if omitted. If STATE is t, return a new state object seeded from the time of day." - (cond ((null state) (cl-make-random-state cl--random-state)) - ((vectorp state) (copy-tree state t)) - ((integerp state) (vector 'cl--random-state-tag -1 30 state)) - (t (cl-make-random-state (cl--random-time))))) - -;;;###autoload -(defun cl-random-state-p (object) - "Return t if OBJECT is a random-state object." - (and (vectorp object) (= (length object) 4) - (eq (aref object 0) 'cl--random-state-tag))) - + (unless state (setq state cl--random-state)) + (if (cl-random-state-p state) + (copy-tree state t) + (cl--make-random-state (if (integerp state) state (cl--random-time))))) ;; Implementation limits. |